Throwing power measurement: The Assaf cell

A new throwing power cell is described in detail; it has the virtue of bein g usable as a small fixture that can be positioned in an electroplating tan k, This so-called Assaf Cell is particularly useful for simulating small re cesses, typically through-holes found in printed circuit boards (PCBs). This paper demonstrates how a Throwing Power Index, given by the ratio of m etal thickness on the front and rear faces of the Assaf-Cell test panel, ma y be used to evaluate/optimize electrodeposition conditions. Data are prese nted from work using various electrolytes, including high-throw acid copper solutions, thereby illustrating its usefulness and application.